Patent GB-332187-A (GB)
Title: Improvements in or relating to the manufacture or treatment of materials made of or containing cellulose esters or ethers
IPC: F16D59/00
Filed: 1929-01-05
Abstract: 332,187. British Celanese, Ltd., and Ellis, G. H. Jan. 5, 1929. Yarns &c., treating with liquids. - Yarns or other materials made of or containing structureless products made of or containing cellulose esters or ethers are manufactured or treated by incorporating in the products during, continuously with or after their production, a solvent or gelling agent for the cellulose derivative and thereafter subjecting the materials to a treatment with dry or substantially dry steam to obtain materials in which the cellulose derivative resists or substantially resists the delustering action of hot aqueous liquids or moist steam. Structureless products made of or containing cellulose esters or ethers are defined as filaments or other products produced from solutions of the cellulose esters or ethers to differentiate them from the structural products obtained for example by direct acetylation or esterification of cotton or other cellulosic fibres without structural alteration. The process may be applied to structureless products made of or containing cellulose esters, for example cellulose acetate, formate, propionate or butyrate, or cellulose ethers, such as methyl, ethyl or benzyl celluloses, or the corresponding condensation products of cellulose and glycols or other polyhydric alcohols and also to the treatment of mixed materials containing such filaments, threads or others products in association with other fibres, for example cotton, the cellulosic type of artificial silk, wool or silk. The solvent or gelling agent may be any substance capable of dissolving or swelling cellulose acetate or other cellulose derivative but should preferably be non-volatile under the conditions of the subsequent treatment, for example, resorcinol, hydroquinone, cresols, diacetone alcohol, diacetin, para-toluene-sulphonamide, and the isomeric xylene sulphonamides and their methyl and ethyl derivatives, diethyl tartrate. pthalimide and mixtures thereof. Agents of much greater volatility may however be employed for example phenol, ethyl lactate, glycol ethers or acetic acid or according to the Provisional Specification acetone. In conducting the process a product consisting of or containing cellulose acetate artificial silk may for example be immersed in a solvent or gelling agent or a solution or dispersion of the same, or a solvent or gelling agent may be applied to the fibre by mechanical means, for example by treatment with a solution or dispersion thereof in a padding mangle. Alternatively the solvent or gelling agent may be dissolved in or form part of the spinning solution employed in the manufacture of the artificial silk. In the case of wet spun products, the solvent or gelling agent may be incorporated in the products continuously with or in the course of their production by employing a solvent or swelling agent in the precipitating bath in sufficient concentration to be carried forward out of the bath by the formed products or by incorporating in the spinning solution itself a solvent or swelling agent less volatile than the non-solvent media in the bath in sufficient quantity to enable it to be carried out of the bath by the products or by leading the products directly from the precipitating bath into a suitable bath containing the desired solvent or gelling agent. As regards the treatment with dry or substantially dry steam, temperatures of about 100‹ C. may be employed but considerably higher temperatures obtained by steam under pressure may be used. The steaming may be carried out continuously with the production of the artificial filaments or products, for example dry-spun artificial filaments after leaving the spinning cells may be caused to pass through a chamber where they are subjected to the action of the steam. In conducting such continuous operations the solvent or swelling agent may be incorporated in the spinning solution itself or may be applied to the filaments or other products during the course of their travel through the spinning cells or outside the spinning cells, for example as described in Specification 326,462. Products wet-spun under such conditions that they retain solvent or gelling agents may be carried with or without intermediate drying into suitable chambers for effecting the steaming. By applying a stretch to the materials either before or during the steaming treatments, particularly by stretching beyond the elastic limit, the modification of the properties may be materially assisted, compare. Specification 277,089. As is indicated in Specification 269,605 when materials which have been delustered by means of hot aqueous media are impregnated with solvents and are treated with dry or substantially dry steam, relustering takes place. This lustering occurs before the modification of the properties rendering the materials substantially non-delusterable according to the present process, which must be carried beyond this mere lustering of the materials. The process may be applied to structureless cellulose acetate filaments or threads of any type, for example flat or ribbon like filaments, semi-round and round filaments and hollow, tubular or voluminous filaments. The products treated may be the normal lustrous products or may be products which have been spun in a lustreless condition or so as to have only a low lustre, or products which have been delustred bv treatment with moist steam or hot aqueous liquids. The solvents or gelling agents introduced into the filaments, threads, yarns, fabrics or other products may, if desired, be removed therefrom, for example by a subsequent washing operation. In examples, cellulose acetate yarn in hank form spun from an acetone solution of cellulose acetate containing 4 per cent of resorcinol is steamed for three-quarters of an hour with dry steam at 5 pounds pressure; structureless cellulose acetate yarn in hank form is treated for two hours at 75‹ C. in a 30 :1 bath containing 12¢ per cent on the weight of the goods of xylene-sulphon-monomethylamide dispersed in twice its weight of 50 per cent turkey red oil, washed off, dried and steamed as in the first example: satin woven fabric made from structureless cellulose acetate yarn is padded in a 20 per cent solution of acetic acid, batched and dried and then steamed for one hour with dry steam at 5 pounds pressure and washed off thoroughly; structureless cellulose acetate varn in hank form is treated for 1¢ hours at 70‹ C. in a 1 per cent aqueous solution of hydroquinone rendered faintly acidic with acetic acid, lifted, hydro-extracted, dried without rinsing and steamed as in the first example, whereupon it is washed off well and dried; fabric made from structureless cellulose acetate yarn is treated in a 30 :1 bath of a 1 per cent aqueous solution of p-toluene-sulphonamide for 2 hours at 75‹ C., washed off lightly, dried and steamed as in the first example. Materials treated as described in the examples, retain their lustre even after boiling for 1¢-2 hours in a 1 per cent soap solution.